The present disclosure relates generally to the field of seating technology and more particularly to the field of recliner mechanisms for adjusting the position of a seat back with respect to a seat cushion.
Generally, two main types of recliner mechanisms are well known for use in automotive vehicle seats. First is the well known pawl and sector recliner mechanism which commonly uses a pivoted pawl connected to or formed in one structure (such as a seat base frame) and a toothed gear sector connected to or formed in another structure (such as a seat back frame). It is also common to have the pawl and sector incorporated in a separate recliner mechanism that interconnects the seat back frame and the seat base frame. Numerous examples of known pawl and sector recliner mechanisms exist.
Second is the also well known round or rotary recliner mechanism. Numerous examples of round heart recliner mechanism also exist such as those disclosed in U.S. Pat. Nos. 4,143,905; 5,536,217; 6,092,874; and 6,805,650. Most of the known rotary recliner mechanisms utilize a cam mechanism and biased movable lock members commonly having teeth. It is also well known to include a biasing member, typically in the form of a spring, or multiples thereof, for biasing the lock members in a locked position. Commonly, an actuator, such as a handle, is used to actuate the cam mechanism to move the lock members, against the force of the biasing member, to an unlocked position where the teeth of the lock member are disengaged with mating teeth on either of the side plates of the rotary recliner mechanism.
For known rotary recliner mechanisms there remains significant drawbacks and inadequacies requiring undesirable tradeoffs in the designs of such mechanisms. Existing rotary recliner mechanisms are still not sufficiently simple and efficient in operation and can include relatively high actuation efforts or will have a low effort actuation mechanism but with an unacceptable amount of slack or “play” as well as being difficult and costly to efficiently manufacture. Accordingly, improvements in recliner mechanisms, and in particular in rotary recliner mechanisms, remains highly desirable.